Characterization factors for terrestrial acidification at the global scale: a systematic analysis of spatial variability and uncertainty

Decentralized municipal solid waste management system (DMSWMS) as an alternative to centralized MSWMS (CMSWMS) for HEIs based on case study of the University of the Punjab, Lahore, Pakistan

Like other parts of the world, the source-specific generation of MSW in higher education institutes (HEIs) of Pakistan contain ≥ 70% compostables being managed through CMSWMS, a resource exhaustive environmental degradation approach. CMSWMS in the University of the Punjab, Lahore- 54590, a mother HEI in Pakistan, includes MSW containing over 2/3rd compostables (with ≥ 85% moisture contents) carrying poor collection efficiency and disposal at distantly located open dumps with linear economy. Here, DMSWMS effectiveness compared to CMSWMS was based on composting compostables at source-level to observe variations in the composition and characteristics of the MSW components, collection efficiency, cost, and combustibles' earlier separation-driven impacts on its drying duration and calorific value for refuse-derived fuel (RDF), and assessing LCA-based acidification potential of carriage and disposal. Compared to CMSWMS, composting-based DMSWMS significantly improved characteristics of the compostables, combustibles, and recyclables. The DMSWMS resulted ≥ 97% collection efficiency, 89% reduction in collection and disposal cost, significant reduction in acidification potential through ≥ 94% GHGEs reduction, and rendered upfront availability of combustibles as RDF with 86% greater GCV. Cumulatively, all the DMSWMS-driven improvisations led the selected HEI in achieving 100% weighing score of MSWM component of the UI Green Metric World University Campus Ranking system. However, for prompting composting-based sustainable DMSWMS at broader scale in a city, multiple studies are required with stakeholders on board from union councils (smallest administrative units analogic to counties), which would streamline DMSWMS integration into MSW sanitation policy framework of municipalities.

Modeling marine microplastic emissions in Life Cycle Assessment: characterization factors for biodegradable polymers and their application in a textile case study

Introduction

With the continuous increase of plastics production, it is imperative to carefully examine their environmental profile through Life Cycle Assessment (LCA). However, current LCA modeling is not considering the potential impacts of plastic emissions on the biosphere. To integrate plastic emissions into LCA, characterization factors are needed that commonly consist of three elements: a fate factor, an exposure factor, and an effect factor. In this context, fate factors quantify the distribution and longevity of plastics in the environment. Research on these fate factors is still limited, especially for biodegradable polymers. Hence, the main objective of this research was to determine the fate factors of biodegradable polymers [poly (lactic acid), poly (butylene succinate), and poly (ε-caprolactam)] based on primary experimental data for the marine environment.

Methods

The validity of former research is tested by comparing the degradation evolution of i. macro- and microplastic particles, ii. two different grades of the polymer, and iii. different temperature levels. The degradation data are obtained by monitoring the oxygen consumption over a period of six months in natural seawater. The determined degradation rates are combined with sedimentation, resuspension, and deep burial rates to obtain fate factors. These fate factors are used to develop polymer-specific characterization factors. The resulting characterization factors are tested in an LCA case study of a synthetic sports shirt made from biodegradable polymer fibers. It allows to assess the relative importance of microplastic impacts compared to other life cycle impacts.

Results and discussion

Comparing the resulting specific surface degradation rates indicates that microplastic degradation rates could be overestimated when using macroplastic degradation data. Pertaining to the case study, the results show that the impact on ecosystem quality by microplastic emissions could account for up to 30% of the total endpoint category. Overall, this work aims to foster interdisciplinary collaboration to leverage the accuracy of LCA studies and thus provide guidance for novel material development.

Ammonia volatilization and nitrous oxide emission and their responses to environmental indicators under different irrigation levels and nitrogen fertilizer synergists

Nitrous oxide (N2O) and ammonia (NH3) emission are the main pathways for gaseous nitrogen loss, which decrease fertilizer utilization while increasing environmental risks. The present research aimed to examine (1) the effect of irrigation amounts and nitrogen fertilizer synergist types on the emissions of NH3 and N2O from winter wheat field in Guanzhong Plain of China; and (2) the responses of them to soil environmental indicators. The study included two irrigation levels: low irrigation (W1) and high irrigation (W2), and four types of nitrogen fertilizer synergist: urease inhibitor (UI), nitrification inhibitor (NI), dual-acting inhibitor (DI), no N synergist (only urea, U), and no nitrogen application (N0). The results showed that the maximum peak of NH3 volatilization under UI and DI treatments was much lower and appeared later than U treatment. The NH3 emission reduction potentials of UI, NI, and DI treatments were 45.61%, 0.44%, and 26.74%, respectively, while their N2O emission reduction potentials were 11.06%, 29.51%, and 32.43%, respectively. The contributions of WFPS, NH4+-N, and NO3--N to NH3 volatilization and N2O emissions were 2.68-5.99%, 72.63-81.96%, and 15.36-20.25% for NH3 volatilization, and 9.76-18.48%, 9.00-34.49%, and 50.79-77.17% for N2O emissions, respectively. Overall, the study results reveal the pathways through which soil environmental factors affect NH3 and N2O emissions, which contribute to the improvement of the application strategies of nitrogen fertilizer synergists to reduce nitrogen losses in agricultural systems.

Life cycle assessment of hybrid alkali-activated cement production with red mud as an alkali activator

The production of hybrid alkali-activated cement (HAAC) has generated considerable interest in environmental issues. In this research, the environmental impacts of utilizing red mud (RM) as a partial activator of alkali-activated ground granulated blast furnace slag (GBFS) in HAAC production have been evaluated. A contribution analysis was carried out using life cycle assessment (LCA) to assess the environmental significance of six important substances in HAAC production. A comparative analysis of the environmental consequences of producing ordinary portland cement (OPC) and two HAACs using various activators in the same plant was conducted. The results showed that the calcination and preparation of alkali-activated cementitious materials are the two processes with the highest environmental impacts. Marine ecotoxicity was identified as the primary impact category, followed by freshwater ecotoxicity and fossil depletion. HAAC provides better benefits than OPC in most environmental impact categories. Additionally, the inclusion of RM as a partial alkali activator to HAAC results in even more pronounced environmental benefits when compared to NaOH alone, particularly in terms of cleaner production areas.

Environmental impact of single-use versus reusable gastroscopes

INTRODUCTION

The environmental impact of endoscopy is a topic of growing interest. This study aimed to compare the carbon footprint of performing an esogastroduodenoscopy (EGD) with a reusable (RU) or with a single-use (SU) disposable gastroscope.

METHODS

SU (Ambu aScope Gastro) and RU gastroscopes (Olympus, H190) were evaluated using life cycle assessment methodology (ISO 14040) including the manufacture, distribution, usage, reprocessing and disposal of the endoscope. Data were obtained from Edouard Herriot Hospital (Lyon, France) from April 2023 to February 2024. Primary outcome was the carbon footprint (measured in Kg CO2 equivalent) for both gastroscopes per examination. Secondary outcomes included other environmental impacts. A sensitivity analysis was performed to examine the impact of varying scenarios.

RESULTS

Carbon footprint of SU and RU gastroscopes were 10.9 kg CO2 eq and 4.7 kg CO2 eq, respectively. The difference in carbon footprint equals one conventional car drive of 28 km or 6 days of CO2 emission of an average European household. Based on environmentally-extended input-output life cycle assessment, the estimated per-use carbon footprint of the endoscope stack and washer was 0.18 kg CO2 eq in SU strategy versus 0.56 kg CO2 eq in RU strategy. According to secondary outcomes, fossil eq depletion was 130 MJ (SU) and 60.9 MJ (RU) and water depletion for 6.2 m3 (SU) and 9.5 m3 (RU), respectively.

CONCLUSION

For one examination, SU gastroscope have a 2.5 times higher carbon footprint than RU ones. These data will help with the logistics and planning of an endoscopic service in relation to other economic and environmental factors.

Effects of Nitrogen Emissions on Fish Species Richness across the World's Freshwater Ecoregions

The increasing application of synthetic fertilizer has tripled nitrogen (N) inputs over the 20th century. N enrichment decreases water quality and threatens aquatic species such as fish through eutrophication and toxicity. However, the impacts of N on freshwater ecosystems are typically neglected in life cycle assessment (LCA). Due to the variety of environmental conditions and species compositions, the response of species to N emissions differs among ecoregions, requiring a regionalized effect assessment. Our study tackled this issue by establishing regionalized species sensitivity distributions (SSDs) of freshwater fish against N concentrations for 367 ecoregions and 48 combinations of realms and major habitat types globally. Subsequently, effect factors (EFs) were derived for LCA to assess the effects of N on fish species richness at a 0.5 degree × 0.5 degree resolution. Results show good SSD fits for all of the ecoregions that contain sufficient data and similar patterns for average and marginal EFs. The SSDs highlight strong effects on species richness due to high N concentrations in the tropical zone and the vulnerability of cold regions. Our study revealed the regional differences in sensitivities of freshwater ecosystems against N content in great spatial detail and can be used to assess more precisely and comprehensively nutrient-induced impacts in LCA.

Global evaluation of inhibitor impacts on ammonia and nitrous oxide emissions from agricultural soils: A meta-analysis

Inhibitors are widely considered an efficient tool for reducing nitrogen (N) loss and improving N use efficiency, but their effectiveness is highly variable across agroecosystems. In this study, we synthesized 182 studies (222 sites) worldwide to evaluate the impacts of inhibitors (urease inhibitors [UI], nitrification inhibitors [NI] and combined inhibitors) on crop yields and gaseous N loss (ammonia [NH₃ ] and nitrous oxide [N₂ O] emissions) and explored their responses to different management and environmental factors including inhibitor application timing, fertilization regime, cropping system, water management, soil properties and climatic conditions using subgroup meta-analysis, meta-regression and multivariate analyses. The UI were most effective in enhancing crop yields (by 5%) and reducing NH₃ volatilization (by 51%), whereas NI were most effective at reducing N₂ O emissions (by 49%). The application of UI mitigates NH₃ loss and increases crop yields especially in high NH₃ -N loss scenarios, whereas NI application would minimize the net N₂ O emissions and the resultant environmental impacts especially in low NH₃ -N loss scenarios. Alternatively, the combined application of UI and NI enables producers to balance crop production and environmental conservation goals without pollution tradeoffs. The inhibitor efficacy for decreasing gaseous N loss was dependent upon soil and climatic conditions and management practices. Notably, both meta-regression and multivariate analyses suggest that inhibitors provide a greater opportunity for reducing fertilizer N inputs in high-N-surplus systems and presumably favor crop yield enhancement under soil N deficiency situations. The pursuit of an improved understanding of the interactions between plant-soil-climate-management systems and different types of inhibitors should continue to optimize the effectiveness of inhibitors for reducing environmental losses while increasing productivity.

Relevance of Impact Categories and Applicability of Life Cycle Impact Assessment Methods from an Automotive Industry Perspective

Climate change impacts have been extensively addressed in academia, politics and industry for decades. However, particularly within the scientific community, the importance of considering further impact categories to ensure holistic environmental assessment and avoid burden shifting is strongly emphasized. Since considering all impact categories might become overwhelming for industry, a prioritization approach can support practitioners to focus their efforts on the most relevant impacts. Therefore, within this paper, an approach for the identification of relevant impact categories is developed for the automotive sector together with Volkswagen AG. The evaluation is conducted using a criteria set including criteria groups “relevance for automotive sector” and “relevance for stakeholders”. For the impact categories identified as relevant, an evaluation of LCIA methods is conducted considering the methodologies CML and ReCiPe 2016 and the methods recommended by PEF. The results demonstrate that climate change is by far the most relevant impact category followed by resource use, human toxicity and ecotoxicity from both automotive and stakeholder perspective. Based on the evaluation of the LCIA methods, a combination of different methods can be recommended. This work provides guidance for the automotive sector to prioritize its focus on the most relevant impact categories and to select applicable LCIA methods for their quantification.

Environmental trade-offs of direct air capture technologies in climate change mitigation toward 2100

Direct air capture (DAC) is critical for achieving stringent climate targets, yet the environmental implications of its large-scale deployment have not been evaluated in this context. Performing a prospective life cycle assessment for two promising technologies in a series of climate change mitigation scenarios, we find that electricity sector decarbonization and DAC technology improvements are both indispensable to avoid environmental problem-shifting. Decarbonizing the electricity sector improves the sequestration efficiency, but also increases the terrestrial ecotoxicity and metal depletion levels per tonne of CO2 sequestered via DAC. These increases can be reduced by improvements in DAC material and energy use efficiencies. DAC exhibits regional environmental impact variations, highlighting the importance of smart siting related to energy system planning and integration. DAC deployment aids the achievement of long-term climate targets, its environmental and climate performance however depend on sectoral mitigation actions, and thus should not suggest a relaxation of sectoral decarbonization targets.

Life Cycle Assessment and Cost Analysis of Additive Manufacturing Repair Processes in the Mold Industry

There is a growing demand for data regarding the environmental and economic performance of additive manufacturing to establish the role of this technology in the future circular industrial economy. This paper provides a comparative analysis of direct energy deposition technology with conventional manufacturing, specifically iron casting, in the context of the repairing capabilities of the direct energy deposition system in a damaged glass bottle mold. Making use of already established methodologies for environmental and economic assessment, a life cycle assessment and a life cycle costing study was conducted on each scenario to provide a holistic perspective on the advantages and limitations of each system. With the gathered life cycle inventory, the main environmental impacts and life cycle costs were determined. The hybrid repairing scenario results show a reduction of the environmental impacts and life cycle costs by avoiding resource consumption in the production of a new mold, with underlying economic advantages identified beyond the calculated results. Through strategic integration based in life cycle approaches, it is concluded that direct energy deposition technology can play a key role in the sustainable development of tooling and manufacturing industries, especially in products with large dimensions, complex geometry, and customized design.

Human Health and Ecosystem Quality Benefits with Life Cycle Assessment Due to Fungicides Elimination in Agriculture

Industrial agriculture results in environmental burdens due to the overuse of fertilizers and pesticides. Fungicides is a class of pesticides whose application contributes (among others) to human toxicity and ecotoxicity. The European Union aims to increase organic agriculture. For this reason, this work aims to analyze climate change, freshwater ecotoxicity, terrestrial ecotoxicity, human toxicity, (terrestrial) acidification, and freshwater eutrophication impacts of fungicides and calculate expected benefits to human health (per European citizen) and ecosystem quality (terrestrial) with life cycle assessment (LCA) during crop production. The Scopus database was searched for LCA studies that considered the application of fungicides to specific crops. The analysis shows how many systemic and contact fungicides were considered by LCA studies and what was the applied dosage. Furthermore, it shows that fungicides highly contribute to freshwater ecotoxicity, terrestrial ecotoxicity, human toxicity, and freshwater eutrophication for fruits and vegetables, but to a low extent compared to all considered environmental impacts in the case of cereals and rapeseed. Expected benefits to human health and ecosystem quality after fungicides elimination are greater for fruits and vegetables, ranging between 0 to 47 min per European citizen in a year and 0 to 90 species per year, respectively.

Nitrogen in Life Cycle Assessment (LCA) of agricultural crop production systems: Comparative analysis of regionalization approaches

Assessing reactive nitrogen (N_r) flows resulting from agricultural crop production systems (ACPS) with LCA requires regionalization. However, methodological approaches for regionalized LCA of ACPS may not necessarily reflect a comprehensive picture of N_r compounds and their complex interaction with the environment. This study presents a comprehensive analysis of the consideration of N_r in methodological approaches for regionalized LCA applied to ACPS. We conducted a review comprehending scientific literature on regionalization approaches applied to ACPS and compared these with general requirements of LCA and the scientific background of the N-cycle following the LCA framework. Special focus was placed on the analysis of process-based models (PBM) and life cycle impact assessment (LCIA) methods. We derived key factors relevant for a regional assessment of N flows in LCA and compared these to 23 regionalization approaches applied to ACPS. Main obstacles identified to conduct a regionalized LCA for ACPS involved the consideration of different regional scales and thus a missing common regionalization approach suitable for ACPS. Although, N related key-factors were mainly considered by the analyzed approaches in the different LCA phases, critical points involved the consideration of N field emissions and N impact assessment. Based on these findings, practical recommendations were given. Our comprehensive review provides relevant requirements for an improved regional N assessment in regionalized LCA of ACPS and aims to present a realistic picture when comparing different alternatives considering N specific regional impacts.

Globally differentiated effect factors for characterising terrestrial acidification in life cycle impact assessment

To assess terrestrial ecosystems damages from acidification, life cycle impact assessment (LCIA) can be applied using characterisation factors, which integrate the quantification of adverse effects via effect factors (EFs), linking decreasing soil pH to declines in species richness. With a species coverage of 0.6%, the currently-existing EFs defined for 14 biomes carry important uncertainties and lack the appropriate spatial resolution to capture the effects of terrestrial acidification. In our study, we thus used georeferenced observational data with 113 million data points to develop a comprehensive, global inventory covering 189,185 vascular plant species, which is nearly 100 times more species than existing inventories used in LCIA (raising the species coverage to 49%). EFs were then calculated for 825 ecoregions. Great spatial variability is observed between ecoregions within a same biome spanning up to 3 orders of magnitude, and EFs developed at biome level tend to underestimate acidification effects. We find up to 2 orders of magnitude differences between our EFs and the ones currently recommended for use in LCIA. These results call for updating current LCIA practice to assess acidification impacts with our more differentiated and environmentally representative EFs and to implement our approach to other site-dependent environmental impacts where large georeferenced datasets exist.

Environmental impact of the cultivation of energy willow in Poland

The purpose of the work is to analyze the structure of the environmental impact of energy willow cultivation (Salix spp.) on plantations of various sizes, divided per materials and processes. The research covered 15 willow plantations, ranging from 0.31 ha to 12 ha, located in southern Poland. It was found, among others, that the so-called processes, i.e. the use of technical means of production, dominate the structure of the environmental impact (EI) related to the cultivation of energy willow, and that the cultivation of energy willow on larger plantations has a much lower environmental impact compared to cultivation on smaller plantations. Also, in the case of the environmental impact of processes, the largest environmental impact was recorded in the human health category, which is mainly associated with the consumption of fuel, i.e. diesel. It was determined, e.g., that the cultivation of energetic willow on larger plantations is characterized by a much lower environmental impact (as per the cultivation area), at approx. 108 Pt, compared to the cultivation on smaller plantations, where the value of the environmental impact is 168 Pt. A decisively dominant position in the structure of the environmental impact (EI), related to the cultivation of energy willow, is held by the so-called processes, i.e. the use of technical means of production. Their share in the total environmental impact decreases from 148.5 Pt in the group of the smallest plantations to 77.9 Pt in the group of the largest plantations.

Fibre-Reinforced Geopolymer Concretes for Sensible Heat Thermal Energy Storage: Simulations and Environmental Impact

Power plants based on solar energy are spreading to accomplish the incoming green energy transition. Besides, affordable high-temperature sensible heat thermal energy storage (SHTES) is required. In this work, the temperature distribution and thermal performance of novel solid media for SHTES are investigated by finite element method (FEM) modelling. A geopolymer, with/without fibre reinforcement, is simulated during a transient charging/discharging cycle. A life cycle assessment (LCA) analysis is also carried out to investigate the environmental impact and sustainability of the proposed materials, analysing the embodied energy, the transport, and the production process. A Multi-Criteria Decision Making (MCDM) with the Analytical Hierarchy Process (AHP) approach, taking into account thermal/environmental performance, is used to select the most suitable material. The results show that the localized reinforcement with fibres increases thermal storage performance, depending on the type of fibre, creating curvatures in the temperature profile and accelerating the charge/discharge. High-strength, high-conductivity carbon fibres performed well, and the simulation approach can be applied to any fibre arrangement/material. On the contrary, the benefit of the fibres is not straightforward according to the three different scenarios developed for the LCA and MCDM analyses, due to the high impact of the fibre production processes. More investigations are needed to balance and optimize the coupling of the fibre material and the solid medium to obtain high thermal performance and low impacts.

On Reduced Consumption of Fossil Fuels in 2020 and Its Consequences in Global Environment and Exergy Demand

As the world grapples with the COVID-19 pandemic, there has been a sudden and abrupt change in global energy landscape. Traditional fossil fuels that serve as the linchpin of modern civilization have found their consumption has rapidly fallen across most categories due to strict lockdown and stringent measures that have been adopted to suppress the disease. These changes consequently steered various environmental benefits across the world in recent time. The present article is an attempt to investigate these environmental benefits and reversals that have been materialized in this unfolding situation due to reduced consumption of fossil fuels. The life cycle assessment tool was used hereby to evaluate nine environmental impacts and one energy based impact. These impacts include ozone formation (terrestrial ecosystems), terrestrial acidification, freshwater eutrophication, marine eutrophication, terrestrial ecotoxicity, freshwater ecotoxicity, marine ecotoxicity, land use, mineral resources scarcity, and cumulative exergy demand. Outcomes from the study demonstrate that COVID-19 has delivered impressive changes in global environment and life cycle exergy demand, with about 11–25% curtailment in all the above-mentioned impacts in 2020 in comparison to their corresponding readings in 2019.

Human health risk and potential environmental damage of organic and conventional Nicotiana tobaccum production

Tobacco is the most widespread non-food crop in the world. In Brazil, tobacco cultivation is one of the main commodities of the southern region. However, its production is associated with environmental impacts and risks to human health, which have yet to be quantified. This paper uses midpoint and endpoint life cycle assessment (LCA) to analyze the potential environmental damage and human health risk associated with agricultural production of conventional Virginia (CV), organic Virginia (OV), and Burley (BU) tobacco varieties. Organic tobacco production substitutes synthetic fertilizers and pesticides with organic compounds in the cropping stage. The results show that for one ton of dried tobacco, BU, CV, and OV emit 1,610, 1,426, and 1,091 kg CO2 eq, respectively. For organic production, greater impacts are linked to the land use (LU) impact category. The endpoint results showed that OV production resulted in a higher potential for human and environmental damage than BU and CV. The drying of green OV and CV tobacco requires the burning of firewood, which emits high levels of particulate matter and is associated with human health (HH) damage. Overall, the HH damage category accounts for 68%, 82%, and 78% of the total score points associated with the production of BU, CV, and OV.

Overview and recommendations for regionalized life cycle impact assessment

PURPOSE

Regionalized life cycle impact assessment (LCIA) has rapidly developed in the past decade, though its widespread application, robustness, and validity still faces multiple challenges. Under the umbrella of UNEP/SETAC Life Cycle Initiative, a dedicated cross-cutting working group on regionalized LCIA aims to provides an overview of the status of regionalization in LCIA methods. We give guidance and recommendations to harmonize and support regionalization in LCIA for developers of LCIA methods, LCI databases, and LCA software.

METHOD

A survey of current practice among regionalized LCIA method developers was conducted. The survey included questions on chosen method spatial resolution and scale, the spatial resolution of input parameters, choice of native spatial resolution and limitations, operationalization and alignment with life cycle inventory data, methods for spatial aggregation, the assessment of uncertainty from input parameters and model structure, and variability due to spatial aggregation. Recommendations are formulated based on the survey results and extensive discussion by the authors.

RESULTS AND DISCUSSION

Survey results indicate that majority of regionalized LCIA models have global coverage. Native spatial resolutions are generally chosen based on the availability of global input data. Annual modelled or measured elementary flow quantities are mostly used for aggregating characterization factors (CFs) to larger spatial scales, although some use proxies, such as population counts. Aggregated CFs are mostly available at the country level. Although uncertainty due to input parameter, model structure, and spatial aggregation are available for some LCIA methods, they are rarely implemented for LCA studies. So far, there is no agreement if a finer native spatial resolution is the best way to reduce overall uncertainty. When spatially differentiated models CFs are not easily available, archetype models are sometimes developed.

CONCLUSIONS

Regionalized LCIA methods should be provided as a transparent and consistent set of data and metadata using standardized data formats. Regionalized CFs should include both uncertainty and variability. In addition to the native-scale CFs, aggregated CFs should always be provided, and should be calculated as the weighted averages of constituent CFs using annual flow quantities as weights whenever available. This paper is an important step forward for increasing transparency, consistency and robustness in the development and application of regionalized LCIA methods.

Environmental responsibility for sulfur dioxide emissions and associated biodiversity loss across Chinese provinces

Recent years have witnessed a growing volume in Chinese interregional trade, along with the increasing disparities in environmental pressures. This has prompted an increased attention on where the responsibilities for environmental impacts should be placed. In this paper, we quantify the environmental responsibility of SO₂ emissions and biodiversity impacts due to terrestrial acidification at the provincial level for the first time. We examine the environmental responsibility from the perspectives of production, consumption, and income generation by employing a Multi-Regional Input-Output (MRIO) model for 2007, 2010, and 2012. The results indicate that ∼40% of SO₂ emissions were driven by the consumption in provinces other than where the emissions discharged. In particular, those developed provinces were net importers of SO₂ emissions and mainly outsourced their emissions to nearby developing provinces. Over the period of analysis, environmental inequality among 30 provinces was larger than GDP inequality. Furthermore, environmental inequality continued to increase while GDP inequality decreased over the time period. The results of a shared income- and consumption-based responsibility approach suggest that the environmental responsibility of SO₂ emissions and biodiversity impacts for developed provinces can reach up to ∼4- to 93-fold the environmental pressure occurred within those provinces. This indicates that under these accounting principles the developed northern provinces in China would bear a much larger share of the environmental responsibility.

Regionalized Terrestrial Ecotoxicity Assessment of Copper-Based Fungicides Applied in Viticulture

Life cycle assessment has been recognized as an important decision-making tool to improve the environmental performance of agricultural systems. Still, there are certain modelling issues related to the assessment of their impacts. The first is linked to the assessment of the metal terrestrial ecotoxicity impact, for which metal speciation in soil is disregarded. In fact, emissions of metals in agricultural systems contribute significantly to the ecotoxic impact, as do copper-based fungicides applied in viticulture to combat downy mildew. Another issue is linked to the ways in which the intrinsic geographical variability of agriculture resulting from the variation of management practices, soil properties, and climate is addressed. The aim of this study is to assess the spatial variability of the terrestrial ecotoxicity impact of copper-based fungicides applied in European vineyards, accounting for both geographical variability in terms of agricultural practice and copper speciation in soil. This first entails the development of regionalized characterization factors (CFs) for the copper used in viticulture and then the application of these CFs to a regionalized life-cycle inventory that considers different management practices, soil properties, and climates in different regions, namely Languedoc-Roussillon (France), Minho (Portugal), Tuscany (Italy), and Galicia (Spain). There are two modelling alternatives to determine metal speciation in terrestrial ecotoxicity: (a) empirical regression models; and (b) WHAM 6.0, the geochemical speciation model applied according to the soil properties of the Harmonized World Soil Database (HWSD). Both approaches were used to compute and compare regionalized CFs with each other and with current IMPACT 2002+ CF. The CFs were then aggregated at different spatial resolutions—global, Europe, country, and wine-growing region—to assess the uncertainty related to spatial variability at the different scales and applied in the regionalized case study. The global CF computed for copper terrestrial ecotoxicity is around 3.5 orders of magnitude lower than the one from IMPACT 2002+, demonstrating the impact of including metal speciation. For both methods, an increase in the spatial resolution of the CFs translated into a decrease in the spatial variability of the CFs. With the exception of the aggregated CF for Portugal (Minho) at the country level, all the aggregated CFs derived from empirical regression models are greater than the ones derived from the method based on WHAM 6.0 within a range of 0.2 to 1.2 orders of magnitude. Furthermore, CFs calculated with empirical regression models exhibited a greater spatial variability with respect to the CFs derived from WHAM 6.0. The ranking of the impact scores of the analyzed scenarios was mainly determined by the amount of copper applied in each wine-growing region. However, finer spatial resolutions led to an impact score with lower uncertainty.

How Many Environmental Impact Indicators Are Needed in the Evaluation of Product Life Cycles?

Numerous indicators are currently available for environmental impact assessments, especially in the field of Life Cycle Impact Assessment (LCIA). Because decision-making on the basis of hundreds of indicators simultaneously is unfeasible, a nonredundant key set of indicators representative of the overall environmental impact is needed. We aimed to find such a nonredundant set of indicators based on their mutual correlations. We have used Principal Component Analysis (PCA) in combination with an optimization algorithm to find an optimal set of indicators out of 135 impact indicators calculated for 976 products from the ecoinvent database. The first four principal components covered 92% of the variance in product rankings, showing the potential for indicator reduction. The same amount of variance (92%) could be covered by a minimal set of six indicators, related to climate change, ozone depletion, the combined effects of acidification and eutrophication, terrestrial ecotoxicity, marine ecotoxicity, and land use. In comparison, four commonly used resource footprints (energy, water, land, materials) together accounted for 84% of the variance in product rankings. We conclude that the plethora of environmental indicators can be reduced to a small key set, representing the major part of the variation in environmental impacts between product life cycles.

Integration of life cycle assessment and regional emission information in agricultural systems

BACKGROUND

Life cycle assessment (LCA) is a compilation and evaluation of the input energy and materials, output emissions and the potential environmental impacts of a product, service or system throughout its life cycle. While methodological issues of LCA are still being developed, much research is being conducted worldwide in order to improve them. One of the important advances in LCA is a regionalised LCA, i.e. the development of regionalised databases, inventories, and impact assessment methods and models.

RESULTS

Regional emission information (REI) was developed and integrated with the characterisation results in LCA of an agricultural product in the study area. Comparison of outcomes obtained with LCA characterisation results that did not include REI shows that the characterisation results taking REI into account are much higher as regards human toxicity, from 0.02% to 0.18%, freshwater ecotoxicity from 89% to 99% and terrestrial ecotoxicity from 8.006% to 26.177%.

CONCLUSION

Results of current LCA studies on agricultural products and systems that do not include REI are under-estimating the life cycle environmental impact. For the LCA of agricultural products and systems, the REI as well as regionalised life cycle inventory data should be developed and integrated into the current LCA approach.

Meta-Analysis of Soybean-based Biodiesel

Biofuel policy changes in the United States have renewed interest in soybean [ (L.) Merr.] biodiesel. Past studies with varying methodologies and functional units can provide valuable information for future work. A meta-analysis of nine peer-reviewed soybean life cycle analysis (LCA) biodiesel studies was conducted on the northern Great Plains in the United States. Results of LCA studies were assimilated into a standardized system boundary and functional units for global warming (GWP), eutrophication (EP), and acidification (AP) potentials using biodiesel conversions from peer-reviewed and government documents. Factors not fully standardized included variations in NO accounting, mid- or end-point impacts, land use change, allocation, and statistical sampling pools. A state-by-state comparison of GWP lower and higher heating values (LHV, HHV) showed differences attributable to variations in spatial sampling and agricultural practices (e.g., tillage, irrigation). The mean GWP of LHV was 21.1 g·CO-eq MJ including outliers, and median EP LHV and AP LHV was 0.019 g·PO-eq MJ and 0.17 g·SO-eq MJ, respectively, using the limited data available. An LCA case study of South Dakota soybean-based biodiesel production resulted in GWP estimates (29 or 31 g·CO-eq MJ; 100% mono alkyl esters [first generation] biodiesel or 100% fatty acid methyl ester [second generation] biodiesel) similar to meta-analysis results (30.1 g·CO-eq MJ). Meta-analysis mean results, including outliers, resemble the California Low Carbon Fuel Standard for soybean biodiesel default value without land use change of 21.25 g·CO-eq MJ. Results were influenced by resource investment differences in water, fertilizer (e.g., type, application), and tillage. Future biofuel LCA studies should include these important factors to better define reasonable energy variations in regional agricultural management practices.